Containers used to transport products such as those listed above are designed with a spherical or cylindrical shape, so that the pressures created by the products are distributed relatively uniformly. In the case of spherical containers, the stresses to be supported by the walls of the container are perfectly uniform.
However, the construction of of a spherical vessel is not simple, aside from the inconvenience that spherical shapes have, where the volumetric capacity is very reduced in terms of the outer occupied space.
In the case of cylindric tanks, though the construction the tank or container is enormously simplified, there is again the inconvenience of inadequate use of space, since the transversal section remains circular and therefore the volumetric capacity is likewise reduced in terms of the outer space occupied by the container.